Pubertal development of estradiol-induced hypothalamic progesterone synthesis

• Published in: Hormones and behavior Vol. 111; pp. 110 - 113
• Main Authors: Mohr, M.A., Wong, A.M., Tomm, R.J., Soma, K.K., Micevych, P.E.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.05.2019
• Subjects: Animals; Astrocytes - chemistry; Astrocytes - drug effects; Astrocytes - metabolism; Brain Chemistry - drug effects; Chromatography, Liquid; Estradiol - pharmacology; Female; Gonadotropin-Releasing Hormone - analysis; Gonadotropin-Releasing Hormone - metabolism; Hypothalamus; Hypothalamus - chemistry; Hypothalamus - drug effects; Hypothalamus - metabolism; Liquid chromatography tandem mass spectrometry; Luteinizing Hormone - analysis; Luteinizing Hormone - metabolism; Nerve Net - drug effects; Nerve Net - metabolism; Neurons - chemistry; Neurons - drug effects; Neurons - metabolism; Progesterone; Progesterone - analysis; Progesterone - biosynthesis; Rats; Rats, Long-Evans; Sexual Maturation - physiology; Tandem Mass Spectrometry; Liquid chromatography tandem mass spectrometry; Progesterone; Hypothalamus
• ISSN: 0018-506X; 1095-6867
• DOI: 10.1016/j.yhbeh.2018.12.007

In females, a hallmark of puberty is the luteinizing hormone (LH) surge that triggers ovulation. Puberty initiates estrogen positive feedback onto hypothalamic circuits, which underlie the stimulation of gonadotropin releasing hormone (GnRH) neurons. In reproductively mature female rodents, both estradiol (E2) and progesterone (P4) signaling are necessary to stimulate the surge release of GnRH and LH. Estradiol membrane-initiated signaling facilitates progesterone (neuroP) synthesis in hypothalamic astrocytes, which act on E2-induced progesterone receptors (PGR) to stimulate kisspeptin release, thereby activating GnRH release. How the brain changes during puberty to allow estrogen positive feedback remains unknown. In the current study, we hypothesized that a critical step in estrogen positive feedback was the ability for estradiol-induced neuroP synthesis. To test this idea, hypothalamic neuroP levels were measured in groups of prepubertal, pubertal and young adult female Long Evans rats. Steroids were measured with liquid chromatography tandem mass spectrometry (LC-MS/MS). Hypothalamic neuroP increases from pre-puberty to young adulthood in both gonad-intact females and ovariectomized rats treated with E2. The pubertal development of hypothalamic E2-facilitated progesterone synthesis appears to be one of the neural switches facilitating reproductive maturation. •The pre-pubertal female hypothalamus is insensitive to estradiol stimulation of progesterone synthesis.•Synthesis of hypothalamic progesterone synthesis increases during puberty.•Estradiol facilitates progesterone synthesis in the adult female hypothalamus.